Talk of tax reform continues, but reducing what you pay on your 1994 return is a do-it-yourself job.

While there are still plenty of opportunities for savings as you complete your tax return, the news is not all good. Be prepared for these changes:- RETROACTIVE TAX HITS. If you're among the 2 percent or so of top earners, the impact of 1993's tax hike hits with a vengeance.

When Congress created new 36 percent and 39.6 percent tax brackets and applied them retroactively for all of 1993, the lawmakers tried to ease the pain by allowing payment of 1993's extra taxes in three installments.

If you took advantage of that offer, prepare for a double whammy. Not only is there no chance to put off any part of the 1994 tax bill, but also you must pay the second installment on 1993's extra taxes - and it's due on April 17.

If you will have a refund on your 1994 return, you can apply it to paying delayed 1993 taxes.

But if you have to write a check to make the installment payment, don't enclose it with your tax return. It has to go to the Internal Revenue Service in a separate envelope, which you should have received along with a payment voucher form.

(And remember, your third installment is due in April of 1996.)

- HEALTH INSURANCE. Don't waste any time searching the tax forms for a place to write off 25 percent of your medical-insurance premiums. That break, available to more than 2 million self-employed workers last year, disappeared because Congress failed to approve legislation to keep it alive.

Lawmakers promise the write-off will be revived and that it will be made retroactive to cover 1994.